what is the differences between whole house surge protectors?

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No. The DISH and the cable grounding block should be directly tied to the central building ground. If the antenna is located close to the electric service entrance, that should be easy to do. There should be installation instructions that came with the dish that discuss correct installation. Or you can find the direction from the manufacturer online.
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snipped-for-privacy@optonline.net wrote:

Damn, I don't need lightning rods? I can just put up 2 or 3 dishes?
Um, do I need the satelite receivers or can I just connect the dish to a VCR?? (I know the VCR doesn't receive satelite, but would it provide lightning protection??)
Or what happens if I don't connect any wires inside the house??
Geez w, I think I'll go into the lightning protection business.

trader and w and I agree that the dish has to be grounded to the power earthing system, just like cable and phone. (Hmm, or I musta misunderstood w.)
--
bud--

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wrote:
Warning to Gary:
Westom, aka W_tom, is a well known usenet kook and has been at this for years. He has been known to post advice, which if followed could easily kill you or a loved one. Get your advice elsewhere. Really.
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That is interesting to know. I haven't lurked here for years and am now back. My Satellite dishes will be 35 feet up on the side of my house and the service panel is on the other side of the house and in the basement. So my ground has to go directly back to the panel? I can use a #14 ground to an electrical box in the attic. (on the other side of the wall I am mounting the satellite dishes to.
I was looking at both of my neighbors dishes mounted on their chimney chases and neither of them has a ground on them. Will this cause there houses to burn down?
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That should read can I use a #14 ground from cable ground block to electrical outlet box.
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You asked that 5 posts back. There was agreement from Bud, Tom and me, that the answer is no. But why do you prefer to ask strangers here rather than follow the directions for the dish you have? Go to the manufacturer's website or any other dish supplier and I'm sure you'll find instructions, diagrams, etc as to how to achieve an acceptable ground that meets code.
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snipped-for-privacy@optonline.net wrote:

I read back through the NEC. If the US-NEC is enforced requirements are - ground block where coax enters the house - #10 (if copper) minimum size ground wire from ground block, run in as straight a line as practicable. Length is not limited (it is for phone and cable). - ground wire attaches anywhere on the power grounding electrode system including the heavy wires to the grounding electrode(s) - "metal structures supporting the antenna" have to be similarly grounded. A dish is not specifically mentioned. You could argue the dish and structure are grounded by the coax to the ground block and that would probably provide protection.
You are not protecting from a direct lightning strike to the dish (contrary to one opinion). Protection from a direct strike would require a heavier dish ground wire with short connection to earth (which would have to be bonded to the power earthing system). And the connection from the dish entry ground block to the power earthing system would have to be short with consideration for the effects of high currents. I believe the earthing is primarily protection from the dish and lead-in getting direct pickup from a near lightning strike.
If the dish was connected only to its own ground rod, there could be thousands of volts between that ground rod (the dish coax) and the power ground if there was a large surge current to earth through the power earthing system or if there was a very near lightning strike.
As trader suggests RTFM?
--
bud--

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Thanks for the info Bud. From my reading on the net the grounding of the dish is for static buildup only.
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A majority who discuss this stuff know only from popular urban myths. Code is concerned with human safety. If any part of the dish gets accidently shorted to live AC power, then the dish must short out that current - trip the circuit breaker - so that humans are not harmed. Code is about human safety. If grounding was only for static electric discharge, then a 32 AWG wire would be more than sufficient.
Code requires the dish to be earthed for human safety reasons. Then we also earth the dish so that direct lightning strikes cause no damage. For the same reason that Ben Franklin earthed lightning rods on wooden church steeples.
Earthing solves many problems. It also eliminates trivial static electric charges. However those charges are made completely irrelevant by protection already inside the receiver. That grounding is also for human safety and for transistor safety (lightning protection). Many who never knew this instead heard someone say it is for static electric discharge. If true, they were grounding dishes and antennas with wire no thicker than human hair - embedding that wire inside the insulation of coax cable.
Just a few reasons why we know so many who fear static charges are totally misinformed yet automatically promote that widely believed myth anyway.
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westom wrote:

So the dish "ground" is to trip a circuit breaker? Another bizarre idea (maybe it is an urban myth).
From the NIST guide: "Surges of a slightly different kind can also happen in parts of other electrical systems that do not directly involve a power line. Examples of these are: the antenna for a remote garage door opener, the sensor wiring for an intrusion alarm system, the video signal part of a satellite dish receiver. Surges in these systems are caused by nearby lightning strikes."
In case that was not clear - surges on satellite coax come from nearby lightning strikes.

A competent ham would never protect their antenna and equipment from lightning with any scheme that has been in this thread.
And the protection envisioned in the NEC is clearly not for lightning protection.
Lightning strikes to a house, for almost all of us, is an extremely rare event. A lightning strike to a dish is similarly rare.
[Apologies if this winds up as a duplicate post]
--
bud--

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bud-- wrote:

When I was a kid, living in the home my father built on top of a mountain (us kids helped), The house had a metal HVAC duct that ran the length of the house in the basement. Whenever lightning struck within a mile or two, a loud pop complete with a spark would come from the ductwork that was some 80 feet long. It would arc to the metal support poles that were attached to the concrete floor. If I was in the basement, it was quite startling to hear the loud pop and a short time later hear a thunder clap. From time to time we would have lightning damage to various things.
TDD
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wrote:

I was wondering how often satellite dishes get hit by lightning. Are there stats?
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Dish strike is a function of what lightning seeks. For example, lightning avoided a 60 foot high tree to strike earth some 40 feet from that tree. Why? Bedrock came closer to the surface where lightning struck. Lightning choose the better (more conductive) path.
In another case, homeowners installed lightning rods. Lightning returned to strike the same bathroom wall. Lightning rods were only earthed by eight foot electrodes in sand. Bathroom wall plumbing connected to deeper and more conductive limestone. Just another example of how prediction is based more on local details.
Asking about the frequency of strikes to dishes is not informative. Best one can do is determine frequency of strikes to homes. More informative are a number of strikes in the neighborhood in the past decade, which items makes a better electrical connection to earth, and variations in geology.
How often does lightning strike? More than 95% of lightning strikes typically leave no apparent indication. Just another fact that makes prediction hard. One observed that white pines also protect like lightning rods. This NY Times article might provide a better grasp: http://query.nytimes.com/gst/fullpage.html?res 0CE3D7103FF93BA25755C0A963958260
However, an answer of the risk to dishes is relevant only with numerous details unique to your neighborhood. Risk to a dish is better understood with lightning history of the past decade unique to your locale.
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You asked that 5 posts back. There was agreement from Bud, Tom and me, that the answer is no. But why do you prefer to ask strangers here rather than follow the directions for the dish you have? Go to the manufacturer's website or any other dish supplier and I'm sure you'll find instructions, diagrams, etc as to how to achieve an acceptable ground that meets code.
I was asking now about the grounding block to a junction box. Why do you want to respond to a strangers post if you have no helpful information?
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And you asked the very same thing and I answered it 9 posts back with the correct answer, that everyone here agrees with:
Q "Thank you, I will do that. I am mounting them in the "A" on the side of my house opposite my attic. My attic has lights in it. Can I just run a wire to bond to one of the metal electrical boxes? Is it code to run a ground wire directly into the electrical box to tie the sats and coax bonding to? "
A "No. The DISH and the cable grounding block should be directly tied to the central building ground. If the antenna is located close to the electric service entrance, that should be easy to do.
There should be installation instructions that came with the dish that discuss correct installation. Or you can find the direction from the manufacturer online. "
And if you think my saying that you should read the dish install directions, go to the manufacturer's website where you can find instructions, diagrams, etc, is unhelpful, then I'm beginning to think there is no hope for you. Time to call an electrician.
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And you asked the very same thing and I answered it 9 posts back with the correct answer, that everyone here agrees with:
Q "Thank you, I will do that. I am mounting them in the "A" on the side of my house opposite my attic. My attic has lights in it. Can I just run a wire to bond to one of the metal electrical boxes? Is it code to run a ground wire directly into the electrical box to tie the sats and coax bonding to? "
A "No. The DISH and the cable grounding block should be directly tied to the central building ground. If the antenna is located close to the electric service entrance, that should be easy to do.
There should be installation instructions that came with the dish that discuss correct installation. Or you can find the direction from the manufacturer online. "
And if you think my saying that you should read the dish install directions, go to the manufacturer's website where you can find instructions, diagrams, etc, is unhelpful, then I'm beginning to think there is no hope for you. Time to call an electrician.
You have too much time on your hands.....let it go. LOL
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Gary
You really have chosen an installation location that is very difficult to protect. If you bond the dish to the Equipment Grounding Conductor (EGC) of your attic lighting circuit then the voltage on that circuit would rise to a very high value during a lightning strike to the dish itself or anything near by. That will jeopardize anything on that circuit that also has a connection to a wire carried utility other than the power lines. It will also jeopardize the circuit itself as a lightning strike will destroy the insulation on the two insulated conductors when the voltage on the circuits EGC rises to a point well above the effective insulation puncture withstand of the cable.
You need to run a conductor of at least the gauge specified in the installation instructions all the way down to the ground. You then install a ground rod and connect the dishes grounding conductor to that rod. Here is the part that you will just hate. You then run a bonding conductor from that ground rod to the electrical Grounding Electrode System located at or near the the electrical panel. The minimum size for that bonding conductor is number six American Wire Gauge under the US NEC but larger would be better.
If you want to improve your homes lightning and surge / spike protection you will run the required bonding conductor around the house buried in the earth. Then as long as you use a bare conductor you will be increasing the earth contact surface area of the Grounding Electrode System.
-- Tom Horne
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I take it your not one of the installers that the sat companies give $100 or so to install these things :)
I never really thought about it before, but you have to wonder how many of the dishes out there are installed even close to the right way and conform to code, etc. Given the restrictions on locating the dish with a clean shot to the sat vs where the house grounding system is located, one would think that doing the ground correctly must be a real bitch in a good percentage of the installs. Yet you see adds all the time for free installation.
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Tom Horne wrote:

TomH missed a coax ground block, required where the dish coax enters the building. If the dish coax goes down to the basement, in Toms scheme the ground block is connected to the ground rod - could be via the #6 wire as it goes past.      ---------------------------- Do you think the NEC minimum #10 wire from the dish to the rod would survive a direct lightning strike?
Phone and cable entry wires can carry a fraction of a lightning strike to the outside wires (there are multiple paths to earth). The NEC, in general, requires the phone and cable entry protectors to connect with a max 20 foot long wire to the power earthing system.( That may not be short enough to protect equipment from high voltage between power and signal wires.) The NEC has *no* maximum length for the connection from a dish coax entry ground block to the power earthing system. I don't see how the NEC intended for it's requirements to protect from a direct lightning strike. Unless there is a dish coax ground block with a short connection to the power earthing system, equipment damage is very likely. If I was a ham radio operator and expected an antenna to be hit by lightning I would have much more elaborate protection. For a rather low 10,000A lightning strike and a very good 10 ohm rod resistance to earth, the rod connection is 100,000V above "absolute" earth potential. Fortunately, for most of us a direct strike is extremely unlikely. And the OP is putting the dish on the side of the house, which should make it a less likely target.
I have concerns that a remote rod (and the dish coax connected to it) could wind up at a very different potential than the power earthing system if there is a strong surge that is earthed (power, phone, cable), or there is a very close lightning strike (ground potential rise). The bond wire certainly helps, but has significant impedance for surges. Increasing the size does not help as much as is expected.
Bottom line - if I was installing a dish on my house I would try to install it low where a direct lightning strike would be not worth worrying about. I would try to bring the coax in near the power service. In any case I would be unlikely to add a ground rod.
--
bud--

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I have to get the dish up high to get over my neighbors roofline for my line of sight.
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